Sylvania



(No Model.)

T. J. DEWEES.

ELECTRIC CABLE. No. 527,414. Patented Oct. 16,1894.

m: NORRIS PEZTEHS c0, PHUYG-LITHO, wAsmNcmN, o c.

UNITED STATES PATENT OFFICE.

THOMAS J. DEWEES, OF PALMYRA, NEW JERSEY, ASSIGNOR TO THE ELEC- TRICCABLE CONSTRUCTION AND MAINTENANCE COMPANY, OF PENN- SYLVANIA.

SPECIFICATION forming part of Letters Patent No. 527,414, dated October16, 1894.

Application filed June 20, 1894. Serial No. 515 ,115. (No model.)

To all whom it may concern.-

Be it known that I, THOMAS J. DEWEES, of the city of Palmyra, county ofBurlington, and State of New Jersey, have invented an Improvement inElectric Cables, of which the following is a specification.

My invention has reference to electric cables, and consists of certainimprovements which are fully set forth in the following I aspecification and shown in the accompanying drawings which form a partthereof.

My improvement has particular reference to the construction of cablesfor electric current and is especially designed to secure highinsulating qualities for the conductors and a low inductive capacity.

In carrying out my invention I employ a cable made up of a series ofwires so as to be flexible, and in which the wires composing the saidcable may be bare wires resting one in contact with the other, or formedof insulated wires in which each insulated wire may convey a separatecurrent. The cables may be made in the form of a rope, or otherwise 2 5have the wires bunched together so as to form a practical and flexiblestructure. The conductors so formed are inclosed in an insulatingwrapping of paper or other fibrous material forming more or less airspaces through- 0 out the cable, and exterior to said insulatingwrapping is an outer casing of metal to shield the inner structure andmake it water proof. I also prefer to arrange within the outer metalliccasing or tubing and exterior to the pa- 3 5 per a moisture absorbentsuch as powdered quick-lime or chloride of calcium. It is desired toleave more or less air space which is thoroughly dried by this moistureabsorbent,

though in practice considerable of the quick l lime may get within thefibrous or paper insulation or sheath during the process ofconstruction. The object is to secure as far as practicable a good dryair space about or in contact with the wires forming the cable con- 4 5ductor. My invention will be better understood by reference to theaccompanying drawings,in which- Figure 1 is a cross section through theend of a piece of my cable where there is a single large flexibleconducting cable; and Fig. 2 is distribution.

a similar View of the cable made up of separate insulated wires.

A is the conducting cable and may be formed in any suitable manner. InFig. 1 this cable is shown similar to any well known rope cable where aseries of small wires is bunched to form several bunches of twistedwires, and these several bunches are strands of the cable and aretwisted together to form a rope structure. In the construction shown. inFig. 2 the cable is made up of a series of. separate insulatedconductors A each one of which is adapted to telephonic or telegraphicThe cable such as shown in Fig. 1 is more especially designed for largepowers such as employed in electric railways and electric lighting.Surrounding this cable (of whatever character it may be) is arranged anirregularly formed sheath of paper or other fibrous material B, formingpreferably air spaces 19 about the cable. In the drawings this inclosingsheath of paper or fibrous material is shown in its preferred form,though it is evident that in the practi- 7 5 cal construction of thecable it will be hardly possible to keep the parts in such symmetricalshape, and the corrugations and air spaces have been somewhatexaggerated in order to more clearly show the principles of theinvention. The construction will however, be substantially the same.

Inclosing the paper or fibrous covering B is an outer casing (Jof lead,which has the property of being flexible, and at the same time 8 isperfectly air tight and moisture proof.

The cable should be supported substantially in a central positionrelatively to the casing O by means of the irregular shape of theinsulating sheath B of paper or fibrous o material. The thickness of thesheath may be greatly varied, as its thickness is immaterial to theprinciple of construction. The spaces D between the paper sheath orcovering B and the outer tube C is filled with a 5 moisture absorbingsubstance such as powdered quick-lime or chloride of calcium, thefunction of which is to absorb all moisture from the air which surroundsthe cable so that the cable is directly inclosed within a cover- I00 ingor atmosphere of thoroughly dry air, which is the best non conductorknown. If the paper sheath B is more or less open, some of the dryingsubstance D will find its way into the air spaces 5, but this will notaffect the general construction and operation of the cable, and is notinconsistent with my invention, though I prefer as far as possible tohave considerable dry air surrounding the cable. The paper sheath orfibrous insulation B may be applied in any suitable manner and may bebound or otherwise secured in position about the cable proper as apreliminary to inclosing the same in the outer metallic tubing of lead0.

A cable of this character will be perfectly flexible and will have thehighest insulation capacity, thereby excellently adapting it to thevarious purposes involving the transmission of electric energy of alltensions. Of course it is evident that the cable A may be a solid bar ifdesired, but such a design is not practical on account of the difficultyof removing and inserting the cable in conduits where such cables arecommonly employed. It is also to be remarked that the cable proper maybe inclosed in an insulating covering if so desired as indicated indotted lines, but this is not necessary, as full and thorough insulationis secured by the construction otherwise described.

While I prefer the construction illustrated, I do not confine myself tothe details thereof, as the same may be modified without departing frommy invention.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. An electric cable consisting of a conductor or conductors throughwhich the current or currents are caused to pass, an irregular inclosingcovering of fibrous material forming air spaces about the said cable, anouter metallic tubing or casing inclosing the said cable and its fibrouscovering, and a moisture absorbing substance interposed between thefibrous covering of the cable and the metallic tube or casing.

2. An electric cable consisting of a conductor or conductors throughwhich the current or currents are caused to pass, an inclosing casing ofpaper or fibrous material arranged in a zig zag or irregular mannerabout the cable forming air spaces about the said cable, an outermetallic tubing or casing inclosing the said cable and its fibrouscovering, and a moisture absorbing substance such as quicklimeinterposed between the paper or fibrous covering of the cable and themetallic tube or casing.

3. The combination of a metallic cable formed of flexible conductors,and inclosing irregular sheath of paper or fibrous material securedabout the said cable in a manner to form air spaces adjacent to thecable, an inclosing lead sheath or outer tubing, and quicklime containedwithin the outer lead tube or sheath and supported by the paper orfibrous covering of the cable.

In testimony of which invention I have hereunto set my hand.

THOMAS J. DEWEES.

WVitnesses:

ERNEST HOWARD HUNTER, O. H. NEwooMB.

